During the manufacturing of yarn products, slivers of fibrous material, disposed in a tangled mass, must be combed to orient the individual fibers in a generally uniform direction. To orient the individual fibers in a generally uniform direction, the sliver mass is combed by a series of faller bars, typically numbering 144. A typical faller bar includes a plurality of combing needles, similar in appearance to a hair comb, that comb the sliver mass to orient the individual fibers in the generally uniform direction. Forces are generated upon the faller bar by pulling the sliver mass through the series of faller bars. These forces are known to break and bend the combing needles on a frequent basis.
Previously, faller bars have been manufactured entirely out of metallic substrates where the combing needles are mounted in the metallic substrate. The metallic faller bar is known to be expensive and difficult to replace when damaged. Therefore, disposable faller bars have been introduced to the industry to reduce the cost of replacing damaged faller bars. Known replaceable faller bars include a support member defining a generally angular shaft having a diameter of less than 6 mm. The sleeve typically includes a rib projecting outwardly that supports a plurality of combing needles used to orient the individual fibers of the sliver mass as set forth above. A sleeve defines a tubular wall having a generally annular opening that receives the support member. Problems with this design arise due to the narrow diameter, of about 6 mm or less of the support member. The faller bar is known to flex and break due to the narrow diameter of the support member. One such faller bar is disclosed in United States Patent Application No. 2002/0069504 where the disclosed support member has a narrow diameter to provide enough sleeve wall thickness to enable the sleeve to be molded over the support member.
In addition, a flexing faller bar has also resulted in defects in the sliver mass. To reduce the amount of flexing characteristic of presently available faller bars, a smaller sliver mass is introduced to the drafting machine, which results in reduced productivity. Because the limited space available inside a drafting machine, it has been impossible to increase the diameter of the support member due to the additional diameter of up to about 2 mm required of the sleeve.
The sleeve heretofore has required a tubular wall thickness of about 2 mm so that the polymers used to form the sleeve can flow through the sleeve mold without producing defects, such as, for example a void in the tubular wall resulting from inadequate flow of material. An increase in diameter of the support member has required the increase in diameter of the sleeve which results in a non-functional faller bar due to the lack of space inside the drafting machine.
Therefore, it would be desirable to produce a faller bar having a sleeve with narrower wall thickness so that an increased diameter of the support member can be introduced to the drafting machine.